There is today a widespread effort to use recycled and waste materials to produce useful products with the object of both producing products at lower cost while making an environmental contribution by using waste materials which would otherwise be discarded into dumps or landfill waste areas.
Such efforts to process waste materials have had limited success, utilizing minimal amounts of selected waste material and have not led to large scale production of a wide range of low cost acceptable composite products.
In this connection, it has been a major problem with such prior art composite materials to use them to obtain products with consistent or uniform quality and desired structural characteristics or specifications or to modify them to control or vary their specifications for different applications.
Many of the prior art processes which combine waste or filler materials with a plastic binder are simply batch processes which discharge a batch mass of hot mixed materials and this hot mass or paste is delivered to a compression mold to be molded under heat and pressure.
Further, such prior art composite material processes usually require some form of chemical additive to effect an acceptable adherence of the mixed waste and plastic particles to provide a useful product.
For example, published European Patent Application EPO 401 885 A1 discloses a process which proposes mixing various solid waste materials particularly wood, thermoplastic and thermosetting synthetic materials, synthetic and natural rubber, synthetic and/or natural fibers, with polyethylene and various quantities of stabilizers, lubricants and chemical seamars or binders. This mixture is then heated into a plasticized mass and routed to a compression mold and molded under high pressure. The only examples given were limited to the use of wood and it was pointed out that without the chemical additives, i.e. the binders, stabilizers and lubricants, it was found that the products produced were unacceptable and would disintegrate.
Again, U.S. Pat. No. 4,033,866, issued Jan. 27th, 1977, discloses a construction material produced from a hot pasty mass which includes waste plastic along with at least one thermoplastic resin and particles of a filler component which have been previously treated by encapsulating them. with a polyethylene or polypropylene wax.
U.S. Pat. No. 5,075,057 discloses the use of scrap plastics which are ground and heated and then dry blended with preheated material selected from reinforcing materials and fillers with the final heated blend then compression molded at elevated temperatures and pressures into a product of predetermined shape. To provide the product with greater strength, the material added to the plastic blend is chemically surface treated prior to the blending.
Another batch process which takes the hot mass of recycled plastic and waste or filler particles from a high intensity mixer and feeds the batch of hot material into a compression mold is disclosed in U.S. Pat. No. 5,497,594. In this case, recycled plastic and waste or filler particles are subjected to particle interaction in the high intensity mixer with the heated mixture delivered to a compression mold for molding under heat and pressure into a shaped product.
U.S. Pat. No. 5,406,768 discloses a product formed from a polymer and wood fiber. In this case, the wood fiber is obtained, for example, from sawdust produced by sawing or milling wood at saw mills. These wood particles are then combined with a polymer, eg. polyvinyl chloride, at high temperatures and pressures and then extruded through an extrusion dye in a linear extrudiate that is cut off into pellets for subsequent use in extruding or injection molding various profiles or products. Such synthetic materials are relatively expensive as the polymer is virgin material and is preferably more than 50 percent of the total weight of the product and the product is limited to those manufactures where wood is desirable.
One of the difficulties of all of the prior art composite materials is the range of products for which they can be used is limited and/or the products produced lack consistent characteristics or quality.
It is the object of the present invention to overcome the limitations of the prior art and to process large volumes of landfill and industrial, commercial and institutional waste, (except organic materials such as food waste, dirty diapers etc., or toxic or chemical or hazardous waste hereinafter EXCEPTED WASTE) into composite plastic materials capable of being extruded, injection molded, or compression molded to consistently produce quality produce with the desired characteristics.
It is a further object to enable the compositions of the composite plastic materials to be accurately controlled and varied to provide the requisite characteristics in the products they are intended to produce.
It is a further object of the invention to be able to produce such materials utilizing essentially all streams of waste other than EXCEPTED WASTE.
In this connection, the invention makes use of streams of construction waste consisting mainly of bricks, slabs of concrete, broken wood skids and the like, broken glass, drywall material and some plastic wastes (also some metal items which are process discarded) by including them in composite materials designed to produce strong or tough products.
The invention also makes use of curb side waste left in blue boxes in many localities which include all plastic used in households on a daily basis, paper materials, some glass (also some metal items which are process discarded) by including them in composite materials as part of the plastic binding materials and fiber content.
The invention further utilizes the streams of industrial waste including rubber waste from belting and tires etc, thermoset plastics, waste diaper material produced in their manufacture, automobile waste such as plastic bumpers, automobile carpet and vehicle interior padding and waste commercial and residential carpets for inclusion in composite materials to produce molded or extruded products having great internal integrity.
The invention further utilizes streams of plastic products from retail stores comprising C.D. players and other products which are defective or failed warranty and are no longer for sale or resale. Such items usually are of about 90% plastic injection molded or extrusion grade materials and some metal which is discarded during processing. These high grade plastics are included in the composite materials as low melting point carriers for the composite materials.
All of such waste rather than being taken to landfill sites is received directly from the various sources by garbage trucks, rear packers, dump trucks, tractor trailers etc.